Psychotic Experiences In Adulthood Research Articles

Conditional associations between childhood cat ownership and psychotic experiences in adulthood: A retrospective study

Ownership of cats in childhood has been inconsistently associated with psychosis in adulthood. Parasitic exposure, the putative mechanism of this association, may be more common with rodent-hunting cats, and its association with psychosis may depend on other environmental exposures. We examined the conditional associations between childhood cat ownership and the frequency of psychotic experiences in adulthood. Adults (n = 2206) were recruited in downtown Montreal to complete a survey about childhood cat ownership (non-hunting or rodent-hunting), winter birth, residential moves in childhood, head trauma history, and tobacco smoking. The frequency of psychotic experiences (PE) was measured with the 15-item positive subscale of the Community Assessment of Psychic Experiences. Associations between exposures and PE were examined in linear regressions adjusted for age and sex. Interactions among variables were explored using a conditional inference tree. Rodent-hunting cat ownership was associated with higher PE scores in male participants (vs. non-hunting or no cat ownership: SMD = 0.57; 95% CI: 0.27, 0.86), but not in female participants (SMD = 0.10; 95% CI: −0.18, 0.38). In the conditional inference tree, the highest mean PE score was in the class comprised of non-smokers with >1 residential move, head trauma history, and rodent-hunting cat ownership (n = 22; mean standard score = 0.96). The interaction between rodent-hunting cat ownership and head trauma history was supported by a post-hoc linear regression model. Our findings suggest childhood cat ownership has conditional associations with psychotic experiences in adulthood.

Reduced amygdala volume mediates the association between developmental trauma and psychotic experiences in adulthood – findings from a population-based cohort

Reduced amygdala volume mediates the association between developmental trauma and psychotic experiences in adulthood – findings from a population-based cohort

Genetic overlap and causal associations between smoking behaviours and mental health

Cigarette smoking is a modifiable behaviour associated with mental health. We investigated the degree of genetic overlap between smoking behaviours and psychiatric traits and disorders, and whether genetic associations exist beyond genetic influences shared with confounding variables (cannabis and alcohol use, risk-taking and insomnia). Second, we investigated the presence of causal associations between smoking initiation and psychiatric traits and disorders. We found significant genetic correlations between smoking and psychiatric disorders and adult psychotic experiences. When genetic influences on known covariates were controlled for, genetic associations between most smoking behaviours and schizophrenia and depression endured (but not with bipolar disorder or most psychotic experiences). Mendelian randomization results supported a causal role of smoking initiation on psychiatric disorders and adolescent cognitive and negative psychotic experiences, although not consistently across all sensitivity analyses. In conclusion, smoking and psychiatric disorders share genetic influences that cannot be attributed to covariates such as risk-taking, insomnia or other substance use. As such, there may be some common genetic pathways underlying smoking and psychiatric disorders. In addition, smoking may play a causal role in vulnerability for mental illness.

Testing the Independent and Joint Contribution of Exposure to Neurodevelopmental Adversity and Childhood Trauma to Risk of Psychotic Experiences in Adulthood.

Exposure to neurodevelopmental adversity and childhood trauma are both independently associated with psychosis. However, there is little research on the mechanism underlying their relationship with each other. The current study investigated both the independent and joint effects of neurodevelopmental adversity and childhood trauma to better understand the etiology of psychosis. A large population-based cohort (N = 3514) followed from birth was assessed on psychotic experiences (PE) at 24 years. Neurodevelopmental adversity included obstetric complications (birth weight, gestational age, in-utero influenza exposure, resuscitation) and developmental impairment (cognitive and motor impairments). Trauma exposure included caregiver and peer inflicted trauma up to 17 years. Multiple regression models tested their independent and interactive effect on PE, and path analysis estimated the indirect effect of neurodevelopmental adversity on PE via trauma. Neurodevelopmental adversity (OR = 1.32, 95%CI: 1.08–1.62) and trauma (OR = 1.97, 95%CI: 1.65–2.36) independently increased the odds of PE. There was also an indirect relationship between neurodevelopmental adversity and PE via increased exposure to childhood trauma (β = 0.01, 95%CI: 0.004–0.024). In particular, peer bullying mediated the association between developmental impairment to PE (β = 0.02, 95%CI: 0.01–0.03). In conclusion, children with neurodevelopmental adversity, in particular those with developmental impairment, are more likely to be exposed to trauma. This new etiological understanding of psychosis suggests that PE may be partially modifiable through reducing exposure to peer bullying, especially in children with developmental impairment.

PTSD as a mediator of the relationship between trauma and psychotic experiences.

Traumatic experiences are associated with a higher risk of psychotic illnesses, but little is known about potentially modifiable mechanisms underlying this relationship. This study aims to examine whether post-traumatic stress disorder (PTSD) symptoms mediate the relationship between trauma and psychotic experiences (PEs). We used data from the Avon Longitudinal Study of Parents and Children to examine whether: PTSD symptoms mediate the relationships between (a) childhood trauma and adolescent PEs (study of adolescent PEs; n = 2952), and (b) childhood/adolescent trauma and PEs in early adulthood (study of adult PEs; n = 2492). We examined associations between variables using logistic regression, and mediation using the parametric g-computation formula. Exposure to trauma was associated with increased odds of PEs (adolescent PEs: ORadjusted 1.48, 95% CI 1.23-1.78; adult PEs: ORadjusted 1.57, 95% CI 1.25-1.98) and PTSD symptoms (adolescent PTSD: ORadjusted 1.59, 95% CI 1.31-1.93; adult PTSD: ORadjusted 1.50, 95% CI 1.36-1.65). The association between PTSD symptoms and PE was stronger in adolescence (ORadjusted 4.63, 95% CI 2.34-9.17) than in adulthood (ORadjusted 1.62, 95% CI 0.80-3.25). There was some evidence that PTSD symptoms mediated the relationship between childhood trauma and adolescent PEs (proportion mediated 14%), though evidence of mediation was weaker for adult PEs (proportion mediated 8%). These findings are consistent with the hypothesis that PTSD symptoms partly mediate the association between trauma exposure and PEs. Targeting PTSD symptoms might help prevent the onset of psychotic outcomes.

T112. PTSD AS A MEDIATOR OF THE RELATIONSHIP BETWEEN TRAUMA AND PSYCHOTIC EXPERIENCES

BackgroundTrauma exposure is linked to the development of psychotic illnesses, but little is known about potentially modifiable mechanisms underlying this relationship. Despite the high prevalence of PTSD symptoms in psychotic illnesses, only a few studies have examined the role of PTSD as a mediator, and these were all cross-sectional. This study aims to examine whether PTSD symptoms mediate the relationship between trauma and psychotic experiences (PE), using data from a large birth cohort study.MethodsWe used data from the Avon Longitudinal Study of Parents and Children (ALSPAC) to test whether: a) PTSD symptoms (at age 15) mediate the relationship between childhood trauma (age 0–14 years) and adolescent frequent or distressing psychotic experiences (age 12–18 years) (study of adolescent PE; n = 2,952), and b) PTSD symptoms (reported at age 24 for traumatic event occurring before age 19) mediate the relationship between childhood/adolescent trauma (age 0–17 years) and incident frequent or distressing psychotic experiences in early adulthood (age 19–24 years) (study of adult PE; n = 2,492).Associations between the variables of interest were examined with logistic regression, and mediation with the parametric g-computation formula. As sensitivity analyses, we i) examined broader and narrower psychotic outcomes, ii) included a measure of psychotic-like experiences at age 14 years as an intermediate confounder in the mediation model for adolescent psychotic experiences, and iii) repeated analyses using imputed data.ResultsExposure to trauma was associated with increased odds of psychotic experiences and PTSD symptoms both in adolescence and early adulthood (p<0.001). The association between PTSD and psychotic experiences was stronger in adolescence (p<0.001) than in adulthood (p=0.03). There was moderate evidence that PTSD symptoms mediated the relationship between childhood trauma and adolescent psychotic experiences (proportion mediated 14%), though evidence of mediation was much weaker for adult PE (proportion mediated 8%).In sensitivity analyses we observed similar results when using imputed data, and when modelling psychotic experiences at age 14 as an intermediate confounding for the adolescent PE outcome. The proportion mediated increased when examining more narrowly defined outcomes (19% for adolescent psychotic disorder).DiscussionThese findings provide some evidence consistent with the thesis that psychotic experiences and disorder can occur consequent to PTSD symptoms after trauma exposure. Targeting PTSD symptoms might help prevent the occurrence of psychotic experiences and disorder in people with a trauma history.

Genetic overlap between psychotic experiences in the community across age and with psychiatric disorders

This study explores the degree to which genetic influences on psychotic experiences are stable across adolescence and adulthood, and their overlap with psychiatric disorders. Genome-wide association results were obtained for adolescent psychotic experiences and negative symptom traits (N = 6297–10,098), schizotypy (N = 3967–4057) and positive psychotic experiences in adulthood (N = 116,787–117,794), schizophrenia (N = 150,064), bipolar disorder (N = 41,653), and depression (N = 173,005). Linkage disequilibrium score regression was used to estimate genetic correlations. Implicated genes from functional and gene-based analyses were compared. Mendelian randomization was performed on trait pairs with significant genetic correlations. Results indicated that subclinical auditory and visual hallucinations and delusions of persecution during adulthood were significantly genetically correlated with schizophrenia (rg = 0.27–0.67) and major depression (rg = 0.41–96) after correction for multiple testing. Auditory and visual subclinical hallucinations were highly genetically correlated (rg = 0.95). Cross-age genetic correlations for psychotic experiences were not significant. Gene mapping and association analyses revealed 14 possible genes associated with psychotic experiences that overlapped across age for psychotic experiences or between psychotic experiences and psychiatric disorders. Mendelian randomization indicated bidirectional associations between auditory and visual hallucinations in adults but did not support causal relationships between psychotic experiences and psychiatric disorders. These findings indicate that psychotic experiences in adulthood may be more linked genetically to schizophrenia and major depression than psychotic experiences in adolescence. Our study implicated specific genes that are associated with psychotic experiences across development, as well as genes shared between psychotic experiences and psychiatric disorders.

Childhood abuse and psychotic experiences in adulthood: findings from a 35-year longitudinal study.

The extent to which exposure to childhood sexual and physical abuse increases the risk of psychotic experiences in adulthood is currently unclear.AimsTo examine the relationship between childhood sexual and physical abuse and psychotic experiences in adulthood taking into account potential confounding and time-dynamic covariate factors. Data were from a cohort of 1265 participants studied from birth to 35 years. At ages 18 and 21, cohort members were questioned about childhood sexual and physical abuse. At ages 30 and 35, they were questioned about psychotic experiences (symptoms of abnormal thought and perception). Generalised estimating equation models investigated covariation of the association between abuse exposure and psychotic experiences including potential confounding factors in childhood (socioeconomic disadvantage, adverse family functioning) and time-dynamic covariate factors (mental health, substance use and life stress). Data were available for 962 participants; 6.3% had been exposed to severe sexual abuse and 6.4% to severe physical abuse in childhood. After adjustment for confounding and time-dynamic covariate factors, those exposed to severe sexual abuse had rates of abnormal thought and abnormal perception symptoms that were 2.25 and 4.08 times higher, respectively than the 'no exposure' group. There were no significant associations between exposure to severe physical abuse and psychotic experiences. Findings indicate that exposure to severe childhood sexual (but not physical) abuse is independently associated with an increased risk of psychotic experiences in adulthood (particularly symptoms of abnormal perception) and this association could not be fully accounted for by confounding or time-dynamic covariate factors.Declaration of interestNone.

Intimate partner violence and psychotic experiences in four U.S. cities

BackgroundA large body of research has established a relationship between trauma exposure, particularly during childhood, and psychotic experiences. Yet, there remains a general lack of research on adult trauma exposure, including intimate partner violence (IPV), as a risk factor for psychotic experiences. The purpose of this study is to investigate the association between IPV and psychotic experiences in U.S. cities. MethodsData were collected from 1615 participants in four U.S. cities. Psychotic experiences were assessed through the World Health Organization (WHO) Composite International Diagnostic Interview (CIDI) psychosis screen along with adapted IPV measures. ResultsFindings revealed that experiencing at least one form of IPV was significantly associated with each of the four psychotic experiences assessed for both men and women. The strongest associations were found for threatening and sexual IPV; physical IPV was not significantly associated with psychotic experiences. Exposure to IPV was associated with more than a tripling of the odds of reporting at least one psychotic experience as opposed to none. Among those exposed to IPV there was between three- to five times the odds of reporting specific subtypes of psychotic experiences. ConclusionThe results expand on prior findings linking psychotic experiences and childhood trauma exposure to include intimate adult exposures. Emotional and sexual IPV appear to be associated with elevated risk for psychotic experiences in adulthood. Even though IPV is more commonly reported by women in the U.S., such victimization appears to have similar associations with psychotic experiences regardless of gender.

Early-life metal exposure and schizophrenia: A proof-of-concept study using novel tooth-matrix biomarkers

BackgroundDespite evidence for the effects of metals on neurodevelopment, the long-term effects on mental health remain unclear due to methodological limitations. Our objective was to determine the feasibility of studying metal exposure during critical neurodevelopmental periods and to explore the association between early-life metal exposure and adult schizophrenia. MethodsWe analyzed childhood-shed teeth from nine individuals with schizophrenia and five healthy controls. We investigated the association between exposure to lead (Pb2+), manganese (Mn2+), cadmium (Cd2+), copper (Cu2+), magnesium (Mg2+), and zinc (Zn2+), and schizophrenia, psychotic experiences, and intelligence quotient (IQ). We reconstructed the dose and timing of early-life metal exposures using laser ablation inductively coupled plasma mass spectrometry. ResultsWe found higher early-life Pb2+ exposure among patients with schizophrenia than controls. The differences in log Mn2+ and log Cu2+ changed relatively linearly over time to postnatal negative values. There was a positive correlation between early-life Pb2+ levels and psychotic experiences in adulthood. Moreover, we found a negative correlation between Pb2+ levels and adult IQ. ConclusionsIn our proof-of-concept study, using tooth-matrix biomarker that provides direct measurement of exposure in the fetus and newborn, we provide support for the role of metal exposure during critical neurodevelopmental periods in psychosis.

Evaluation of bullying in persons with different risk for psychosis

Introduction: Emerging research suggests that being exposed to bullying during childhood can increase the risk of psychotic experiences in adulthood. Aggressive peer relations among adolescents are more frequent in boys, both for being victims or perpetrators. Aim: To evaluate whether bullying was more prevalent among Serbian clinical population of patients with psychosis in comparison to their healthy siblings and controls, and to analyze gender differences regarding bullying. Material and methods: This cross-sectional study evaluated schizophrenia spectrum patients (n = 52, age = 29.3 ± 5.9 yrs, in remission, illness duration <10 yrs), their healthy siblings (n = 55, age = 28.6 ± 6.8 yrs) and controls (n=50, age=25.3±1.5 yrs). The subjects fulfilled the bullying questionnaire, five item self-rating scale. Descriptive statistics and Mann-Whitney nonparametric test were used to analyze the data. Results: Compared to their healthy siblings, the patients were more likely to report that they were bullied (patients: 7.0 ± 3.5, siblings: 5.2 ± 2.0, p = 0.000), but patients also bullied others more (patients: 1.4 ± 0.8, siblings: 1.1 ± 0.4, p = 0.02). Comparing the group of patients and controls, we did not find statistically significant difference in any category. The male gender brings higher risk of being physically bullied which has been proven for all examined groups (patients- p = 0.03, controls and siblings- p = 0.00). Conclusion: Aggressive peer relations possibly contribute to the evolution of psychosis, as they were more prevalent in patients in comparison to their healthy siblings, particularly in males. Improved prevention of bullying and use of treatments against its psychological consequences might be one of the possible methods to ameliorate the course of psychosis.

Maternal prenatal infection, early susceptibility to illness and adult psychotic experiences: A birth cohort study

BackgroundExisting evidence has established that maternal infection during pregnancy and illness during early life are associated with later schizophrenia. No research has examined how the combination of these prenatal and postnatal exposures is linked to an increased risk to later schizophrenia and psychotic disorders. MethodsParticipants from the Mater University Study of Pregnancy (MUSP), an Australian based, pre-birth cohort study were examined for lifetime DSM-IV positive psychotic experiences at 21years by a semi-structured interview. Structural equation modelling was used to derive a general factor of psychotic experiences at age 21. Next, we undertook a number of separate analyses to investigate how prenatal infections and infant illness susceptibility are related to positive psychotic experiences in early adulthood, allowing for tests of moderation and mediation between the two risk factors. ResultsAfter adjustment for important confounders, infant illness susceptibility was found to play a mediating role in the association between prenatal vaginal infection and later psychotic experiences. Whereby, infant illness susceptibility showed a direct association with psychotic experiences, while prenatal vaginal infection indirectly predicted psychotic experiences via infant illness susceptibility. ConclusionOur findings suggest that illness susceptibility in early infancy may be central to the relationship between prenatal vaginal infection and later psychotic experiences. Further research is needed to establish the mechanisms that link these prenatal and postnatal exposures with psychotic illness in later life.